Levi l



. TATESV LEVI L. BURDON, OF PROVIDENCE, RHODE ISLAND.

INGO'T F OR GOLD-PLATED WIRE.

SPECIFICATION forming part of Letters Patent No. 294,722, dated March 4, 1884,

Application filed September li2,1883. (No model.)

To all whom it 77mg concern:

Be it known that I, LEVI L. BURDoN, a citizen of the United States, residing at Provideuce, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Ingots for Gold- Plated Wire and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

My invention relates to a certain new and improved process or art which is used in making gold-plated wire 5 and it consists in the improved method of forming or constructing the ingot, which latter is-composed of a seamless drawn or rolled gold tube adapted to receive therein a base-metal core, both parts being then united by solder, all as will be more fully hereinafter set forth.

In the accompanying sheet of drawings, Figure 1 represents a longitudinal central section through my improved ingot after being soldered and preparatory to being drawn down into wire. Figs. 2 and 3 represent, respect ively, in longitudinal section the seamless drawn gold tube and base-metal core. Fig. 4 represents in longitudinal central section the said tubeand core in position for soldering, showing the tube extending vertically above the core, and forming at thetop a space or chamber for retaining the solder preparatory to being heated and united. Figs. 5 and 6 represent cross-sectional views of ingots having different thicknesses of gold tubing or plate. Fig. 6} represents longitudinal and cross sectional views of an ingot having a hollow core.

The object of my invention is to produce an ingot susceptible of being drawn down into iine wire, the latter retaining its exact proportions of gold and base metal which it had in the ingot.

I am aware that it is not new to make compound ingots adapted to be drawn down into wire, and I therefore do not claim such, broadly.

My invention resides, mainly, in the peculiar manner of constructing and forming the ingots.

The following is a detailed description of my invention A in the drawings represents the ingot complete as composed of the solid core 0, sur

rounded by the gold shell B. The latter isformed by a suitable process, which gives it a practically perfect tubular shape and having any desired thickness and diameter, thereby making the metal perfectly homogeneous, and without blow-holes, pits, or seams, which de fects are common to castingots. Further, such drawn tubes can be produced having less thickness atless cost, combinedwith greater strength, than cast tubes or ingots. The core (3 is made of copper or other suitable metal, and turned off true and smooth, its diameter corresponding to the bore of the gold tube to which it is to be soldered. I make the core somewhat shorter than the tube'B, (see Fig. 4,) thereby forming a space or chamber, cl, at the top end of the ingot. The object of this chamber is to retain solder therein while the ingot is being heated in the furnace. The surfaces of the parts B G are suitably prepared and placed (the core being within the tube) vertically in a suitably-heated furnace, which melts the solder within the said chamber d and allows it to flow down and around the said surfaces, thus perfectly uniting them together. After cooling, the ingot is then squared off, as shown in Fig. 1, when it is ready to be drawn down into wire by means of a suitable draw plate or roll. During the latter process, however, the ingot should be annealed after a few passes through said plate.

Another part of my invention, as before stated, consists of an annular ingot or an ingot having a hollow core. (See Fig. 6%.) The manner of constructing this ingot A is practically the same as before describcd I am enabled by the use of hollow ingots to draw down. wire more readily and with a less number of annealings than in the former case.

In practice I prefer making my improved ingots about one and one-fourth inch in diameter outside and about eight inches long.

For certain uses, where very thin plate-wire is required, I turn off the outside of said ingot before drawing until the desired proportion is obtained, thereby adapting it for thinner plated wire than can be obtained by casting or any other known method.

The. tube employed in my ingot may be of fine gold or any suitable alloy.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

The method herein described ofmaking metallic compound ingots, which consists, first, in inserting the suitably-prepared metallic core within the seamless tube, the latter extending beyond the end of said core to form a space or chamber; secondly, placing solder within said chamber, then introducing the whole into a suitably-heated furnace, thereby fusing said solder, thus uniting or welding the core and tube together; and, lastly, withdrawing the ingot from the furnace, after which it is adapted to be drawn or reduced to the required size, substantially as and for the purpose set forth.

In testimony whereof I have affixed my signature in presence of two witnesses.

LEVI L. BURDOX.

Witnesses:

Gno. H. REMINGTOX, Onixnilns HAXNIG A N. 

